A pantograph is also referred to as a bow collector, is an electrical device for a high speed train to receive electric energy from a contact network, and is installed on a train roof. It is named because the rhombic pantograph seems like an opened bow as seen from the side. The pantograph is generally divided into a single arm pantograph and a double arm pantograph, and at present what is frequently used is the single arm pantograph. A carbon slide plate is a key component of the pantograph. When a train runs, the carbon slide plate and a train line slide plate are mainly in contact with a contact wire. Carbon slide plates used at the market at present are mainly a pure metal slide plate, a powder metallurgy slide plate, a pure carbon slide plate and a dip metal slide plate. The pure carbon slide plate becomes a slide plate special for high speed rails such as a train with the speed exceeding 200 Km per hour due to its characteristics of abrasion resistance, high conductivity, corrosion resistance and high temperature resistance and the like.
In the running process of the high speed train, the carbon slide plate needs be consumed in order to protect the contact wire. The service life of the carbon slide plate is relevant with the speed. The carbon slide plate needs to be replaced after about a trip of the Wuguang high speed rail, or else the pantograph cannot be in good contact with the wire, which leads to too long off-line time and affects the running of the high speed rail. As a result, the number of the consumed carbon slide plates is especially large. Along with subway construction in full swing in each city at home and the opening up of inter-city trains, the number of used carbon slide plates is further increased.
The carbon slide plate is composed of multi-section radians, has a length of 1.5 m and a thickness of only 40 mm, and belongs to long and narrow workpieces. Accordingly, existing carbon slide plate production is in a one-time casting forming mode at home and abroad. Since poor impurities are generated easily in the casting process to lead to waste products and four sides need to be machined due to the fact that the cast surface is poor in smooth finish, not only is the waste severe, but also the production efficiency is low. Moreover, the carbon slide plate belongs to brittle materials and it is difficult to clamp a narrow and long workpiece; particularly, the machining of a middle curve groove needs to be kept consistent with the internal radian; however, the secondary clamping during the machining has a harmful effect of dimensional accuracy.